In this article, the thermal performance of a parabolic trough solar air heater (PTSAH) with U-shaped heat exchanger is evaluated. The heater's examined by using copper and aluminum exchangers (UHX) without fin alternately, inside absorber tube placed at focal length nickel-coated stainless steel trough. system in form temperature difference achieved outlet for both efficiency. It observed that better than exchanger. Further, it has been found efficiency increased 9.29% high flow rate use...

Abstract The milled fly ash (MFA) was attained by mechanical ball milling of raw (RFA) and characterized for changes in particles morphology, size, specific surface area (SSA). RFA MFA, varying wt% from 20 to 35, were exclusively used composite fabrication using compression molding machine. (MFC) specimens assessed the tribo‐performance comparison with (RFC) commercial truck brake (CTBC) under loads ranging 125 200 N at 3.3 5 m/s sliding velocity. characterization study showed that glassy...

surrounding temperature employed in classical Gouy-Stodola equation for the irreversibility determination. The components of any system do not transfer heat at all times and thus some error is involved analysis, as conventional calculates using temperature. use effective provides more accurate measurement exergy destruction. R1234ze refrigerant this study due to its low Global Warming Potential (GWP) zero Ozone Depletion (ODP) compared with counterpart R134a. conducted a fixed 10 kW cooling...

An experimental study of air heating system was carried out using a parabolic trough collector with U-tube aluminium heat exchanger. evacuated tube placed at the focal length collected solar radiations reflected from surface trough. The used as working fluid, which heated by passing it through U-shaped exchanger inside tube. It found that efficiency depends on mass flow rate, intensity and use fins. observed fins high rate 4.557 kg/h, maximum temperature 126°C achieved is 13.27% more than...

Thermal effect in elastohydrodynamic lubrication (EHL) has been the subject of study for last four decades; however, some important aspects related to physical behaviour lubricant response pressure, temperature, and shear rate remain largely neglected. This paper presents a brief review thermal EHL literature sheds light on importance accurate characterization properties such as viscosity, density, rheology, conductivity. Full line contact simulations under steady-state transient conditions...

A new central film thickness formula pertaining to thin elastohydrodynamic lubrication (EHL) line contacts has been developed for Carreau-type shear-thinning lubricants using an extensive set of full EHL simulations. The correction factors available in the literature are based on simulations carried out a particular value load and piezo-viscous coefficient simplest exponential pressure–viscosity relationship. In present work, therefore, varied over wide range so as arrive at more generic...

Abstract The performance of an ejector-assisted condenser outlet split dual-evaporator cycle is compared with a conventional albeit consisting pressure reducing valve. cycles do not employ any separator due to its inability efficiently separate the liquid and vapor phases. comparison both has been made for same cooling capacity in low-temperature evaporator unit flow rate R134a R1234yf as refrigerants. impacts changing operating temperatures have examined current investigation. study reveals...

Full EHL line contact simulations have been carried out to obtain a new minimum film thickness formula pertaining thin contacts for Carreau-type shear-thinning lubricants. The present analysis uses Doolittle’s free volume based viscosity model with Tait’s equation describe the density–pressure relationship. load parameter ( W) used in ranges from 2 × 10 −5 5 −4 , while piezo-viscous coefficient varies 15 30 GPa −1 using different sets of Doolittle–Tait parameters. curve-fitted values are...

The present work investigates the usefulness of milled fly ash, prepared by 60 h mechanical milling raw for application brake friction composites. Two specimens were reinforcing 80 wt% and ash with 20 phenolic resin. influence on wear performance developed composite (RFC) (MFC) investigated at varying sliding velocity from 2.6–10.4 ms−1 under 50 N 150 using monitoring apparatus. It was revealed surface morphology powder that large size spherically shaped particles turned in to small rough...

Abstract The performance of a dual evaporator cycle using ejector is compared with conventional employing pressure reducing valve. In both the systems, high temperature considered as flooded evaporator, thus separator employed after evaporator. However, low kind dry comparison i.e., and assisted, done for same cooling capacities dryness fraction at exit R134a, R152a, R1234yf refrigerants. effects varying states refrigerant temperatures evaporators condenser are analyzed Engineering Equation...

The effect of milled fly ash on the tribological response brake friction composites is studied. Two specimens were developed using raw (RFA) and (MFA) tested for wear performance at different loads (50-100 N) with sliding velocities varying from 1.7 to 3.3 m/s. It was observed that spherically shaped RFA particles transformed into rough uneven after ball milling. particle size range found be 22.05-206.19 μm before milling which reduced 3.02-40.64 while specific surface area increased 138.23...

This paper addresses a largely ignored aspect pertaining to the elastohydrodynamic lubrication (EHL) traction behavior of fragile lubricants which undergo transition glassy state at typical EHL contact zone pressures. For such lubricants, conventional model predicts extremely high and unrealistic values coefficient, especially under near pure rolling conditions where thermal effect is negligible. Therefore, an incorporating limiting shear stress associated wall slip phenomenon presented...

The effect of milled fly ash on the tribological response brake friction composites is studied. Two specimens were developed using raw (RFA) and (MFA) tested for wear performance at different loads (50-100 N) with sliding velocities varying from 1.7 to 3.3 m/s. It was observed that spherically shaped RFA particles transformed into rough uneven after ball milling. particle size range found be 22.05-206.19 μm before milling which reduced 3.02-40.64 while specific surface area increased 138.23...

Abstract This study compares the exergy of an ejector‐based two evaporator cycle (EB‐TEC) with a conventional (C‐TEC). The analysis utilizes modified Gouy–Stodola equation, which provides more accurate insight system irreversibility compared to standard formulation. Furthermore, comparison includes three working fluids, that is, R134a, R1234ze, and R600 in both cycles. examines effects varying evaporators condenser temperatures dryness fraction at exit Evaporator 1. data is analyzed using...